Syrian army's statement came nearly a week after the opposition accused the Syrian government air force of firing toxic gas on the rebel-held town of Khan Sheikhoun in Idlib province.

Postol further noted in his report, "I believe it can be shown, without doubt, that the document does not provide any evidence whatsoever that the USA government has concrete knowledge that the government of Syria was the source of the chemical attack in Khan Shaykhun".

Assad insisted it was "not clear whether it happened or not, because how can you verify a video?".

Tests have confirmed sarin gas was used in Khan Sheikhoun, Syria. The Britain-based Syrian Observatory for Human Rights monitoring group reported 25 SDF fighters were killed in the last two days of battle, while the activist-run Raqqa is Being Slaughtered Silently group said on Wednesday that three days of mourning were to be held in a border town held by the SDF after the arrival of the bodies of 15 fighters from the battle. He said the strike "opens new disturbing scenarios for all", considering that there was no thorough investigation into the chemical attack.

Assad said he would only allow an "impartial" external investigation of last week's suspected chemical attack. "These have tested positive for the nerve agent Sarin, or a Sarin-like substance", the delegation said during a special session at the Organisation for the Prohibition of Chemical Weapons in The Hague.

The toxic gas attack, which killed scores of people including children, prompted a United States cruise missile strike on a Syrian air base and widened a rift between the USA and Russian Federation, a close ally of Assad's in his conflict with rebels and militants.

"The United Kingdom therefore shares the U.S. assessment that it is highly likely that the regime was responsible for a sarin attack on Khan Sheikhun on the 4th of April", Ambassador Matthew Rycroft told the UN Security Council.

Meanwhile, the Syrian government has fiercely denied using or even possessing chemical weapons since the country's compliance with the Chemical Weapons Convention was certified by worldwide observers in 2013. The American leader also announced a missile strike targeting an air base believed to be the source of the chemical weapons used in the attack. The delegation's mission is to unequivocally confirm whether or not chemical weapons were utilized without blaming any specific entity. Its findings, expected in 3-4 weeks, will be passed to a joint United Nations-OPCW investigation tasked with identifying individuals or institutions responsible for using chemical weapons.

Global investigators have concluded that sarin, chlorine and sulphur mustard gas have been used in Syria's 6-year-old conflict, with government forces using chlorine and Islamic State militants using sulphur mustard.

RELATED NEWS

Lawyers: Don't rush Arkansas executions decision
District Judge Kristine Baker issued stays Saturday so the inmates could pursue a claim that they could suffer "severe pain". It's also unclear whether the move would prompt action from the state's Judicial Discipline and Disability Commission. 4/18/2017

Man punched, kicked during traffic stop speaks out
Be proactive - Use the "Flag as Inappropriate" link at the upper right corner of each comment to let us know of abusive posts. Hollins says he recognized Bongiovanni from a stop last summer where he says the officer choked and punched him in the face. 4/17/2017

Mark Hamill: Carrie Fisher Star Wars tribute is 'therapy'
Earlier on Friday, Kennedy confirmed that The Last Jedi will be Carrie's last Star Wars film. "She's owned by them", he said. Disney CEO Bob Iger said in March that the filmmakers were "not changing (The Last Jedi) to deal with her passing". 4/17/2017

And the F-Pace has the Best Design too
The decision on these awards is taken by 75 influential motoring journalists from across 24 countries. Jaguar's F-PACE has been awarded best and most attractive vehicle in the 2017 World auto Awards. 4/15/2017

Iran election: President Rouhani registers to run again
During the previous presidential election in June 2013, Rouhani garnered 50.7 percent of a total of over 36 million votes. Rouhani has arrived at the Interior Ministry where candidates enroll, Trend correspondent reported April 14. 4/15/2017

Obama-Era Ozone Rule Remains in Place, for Now
But Pruitt's visit to a mine as the EPA's leader also generated outrage for area environmental groups. Additionally, the group asked the EPA to consider a 90-day freeze on implementing the rule. 4/15/2017

Bulls, Pacers grab last 2 spots in NBA playoffs
So, we get.500 teams making the playoffs, and some pretty boring first-round match-ups. "Now it's about winning some games". At one point, Brooklyn was down by 21 points, as the Nets trailed the Bulls 43-22 with five minutes left in the first half. 4/14/2017

United States drops 'mother of all bombs' on IS in Afghanistan
Testifying before the Senate Armed Services Committee in February, General John Nicholson warned of a stalemate in the country. According to US officials, most of the members of the local Islamic State branch are Pakistani and Uzbek militants. 4/14/2017

Removal of United passenger shines light on airport police
Chicago's Aviation Department said on Wednesday that two more officers had been placed on leave in connection with the incident. United CEO Oscar Munoz has publicly apologized and promised a review of the airline's procedures. 4/14/2017